密集液体中的不可逆波兹曼采样器:弱合近似和模式合理论
Federico Ghimenti1, Ludovic Berthier2,3, Grzegorz Szamel4
1<a href="https://ror.org/032w6q449">Laboratoire Matière et Systèmes Complexes (MSC)</a>, <a href="https://ror.org/05f82e368">Université Paris Cité</a> and CNRS (UMR 7057), 75013 Paris, France.
Physical review. E
|October 19, 2024
概括
将横向力添加到平衡的朗格温过程中,可以加速采样到博尔兹曼稳定状态. 这项研究量化了这种动态加速在一个简单的液体,发现它取决于温度和运输系数.
科学领域:
- 统计力学 统计力学
- 非平衡的动力学.
- 计算物理 计算物理
背景情况:
- 平衡状态的统计力学描述了处于热平衡状态的系统.
- 兰格温过程模型粒子动力学受随机力的影响.
- 非平衡系统表现出复杂的动态,不受博尔兹曼统计的约束.
研究的目的:
- 在兰格温过程中使用横向力研究博尔兹曼平稳态采样加速.
- 量化横向力对简单液体动态加速度的影响.
- 分析横向力,运输系数和温度效应之间的关系.
主要方法:
- 模拟一个简单的液体在三维受到双向横向力.
- 在弱合状态 (高温) 中分析标记粒子的动态.
- 开发和应用一个非平衡模式合理论来捕捉横向力的影响.
主要成果:
- 横向力系统地加速接近博尔兹曼稳定状态.
- 动态加速与增加的奇数传输系数 (移动性,扩散性) 相对应.
- 加速度随着越过交叉的温度增加而降低,特别是在玻璃过渡附近.
结论:
- 横向力为Langevin动态中的加速博尔兹曼抽样提供了一个最小的框架.
- 开发的非平衡模式合理论准确地预测了观察到的加速.
- 这些发现为控制和理解物理系统中的非平衡动态提供了洞察力.
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